TITLE: Safety roadway delineator effective during rainy night-time driving
conditions
United States Patent 4772155
ABSTRACT:
A safety roadway delineator includes one or more elongate recessed
marker surfaces which are coated with a reflective material, preferably
a retroreflective material such as reflective glass beads. The recessed
marker surfaces are vertical or at least inclined to the horizontal to
insure water run-off and are formed either directly in cast-in-place
concrete roadway members or in pre-cast polymer concrete facing panels
which are attached to the cast-in-place concrete roadway members. The
roadway delineator is substantially continuously protected from normal
wear and reliably exhibits reflectivity both under dry and rainy
weather conditions.
INVENTORS:
Dinitz, Arthur M. (New Rochelle, NY)
APPLICATION NUMBER: 07/001890
PUBLICATION DATE: 09/20/1988
FILING DATE: 01/09/1987
ASSIGNEE: Transpo Industries, Inc. (New Rochelle, NY)
PRIMARY CLASS: 404/7
OTHER CLASSES: 359/536, 359/540, 404/6, 404/14
INTERNATIONAL CLASSES: E01C11/22; E01F9/03; E01F9/053; (IPC1-7): E01C11/22; G02B5/128
FIELD OF SEARCH: 404/6-9, 404/12-16, 256/1, 256/13.1, 350/97, 350/100-107
US PATENT REFERENCES:
4348133 Median barrier construction September, 1982 Trent et al.
256/13.1
4000882 Contrasting marker panel for highway guardrails and the like
January, 1977 Penton 404/9
3396639 Reflecting devices August, 1968 Lemelson 404/14
3203327 Cast metal street curb August, 1965 Daley 404/7
3037433 Prefabricated curb sections June, 1962 Maher 404/7
2345644 Light reflecting sign or marker April, 1944 Weber 404/7
FOREIGN REFERENCES:
DE2459500 June, 1976404/7
FR1093411 May, 1955 404/9
FR1291739 March, 1962 404/7
FR1602242 September, 1970 404/7
FR2557896 July, 1985404/14
GB401337 November, 1933 404/7
GB450866 July, 1936404/9
GB453269 September, 1936 404/9
GB492788 September, 1938 404/7
GB497245 December, 1938 404/7
GB500680 February, 1939 404/7
GB513358 October, 1939404/7
GB540023 October, 1941404/12
GB613077 November, 1948 404/7
GB1209646 October, 1970404/7
GB2118999 November, 1983 404/14
PRIMARY EXAMINER: Novosad, Stephen J.
ASSISTANT EXAMINER: Letchford, John F.
Attorney, Agent or Firm:
Lilling & Greenspan
CLAIMS:
What is claimed is:
1. A safety roadway delineator comprising an elongate roadway member
forming a barrier extending along and at least partially defining the
roadway; a pre-cast member made of polymer concrete having an exterior
surface facing the roadway and exposed to roadway traffic, said
pre-cast member being provided with a generally elongate marker surface
recessed in relation to said exterior surface, said marker surface
extending along the length direction of said roadway member and being
inclined in relation to the horizontal to cause water runoff;
reflection means applied to said recessed marker surface for at least
partially reflecting incident light in the direction of the source of
incident light on the roadway; and means for attaching said pre-cast
member to the roadway member, whereby said roadway member forms a
substantially continuous reflective delineator which is protected from
normal wear and reliably exhibits reflecting properties both under dry
and rainy weather conditions.
2. A safety roadway delineator as defined in claim 1, wherein said
roadway member comprises a roadway curb facing.
3. A safety roadway delineator as defined in claim 1, wherein said
roadway member comprises a bench panel used in a tunnel.
4. A safety roadway delineator as defined in claim 1, wherein said
roadway member comprises a median barrier.
5. A safety roadway delineator as defined in claim 1, wherein said
roadway member comprises a bridge protector.
6. A safety roadway delineator as defined in claim 1, wherein said
reflection means comprises retro-reflective means.
7. A safety roadway delineator as defined in claim 1, wherein said
roadway member includes at least two recessed marker surfaces spaced
from and parallel to each other and each provided with reflection
means.
8. A safety roadway delineator as defined in claim 7, wherein said two
recessed marker surfaces are disposed at different angles in relation
to the horizontal.
9. A safety roadway delineator comprising an elongate roadway member
forming a barrier extending along and at least partially defining the
roadway; a pre-cast polymer concrete member having an exterior surface
facing the roadway and exposed to roadway traffic, said pre-cast member
being provided with a generally elongate marker surface recessed in
relation to said exterior surface, said marker surface extending along
the length direction of said roadway member and being inclined in
relation to the horizontal to cause a water run-off; microsphere
reflection means applied to said recessed marker surface for at least
partially reflecting incident light in the direction of the source of
incident light on the roadway; and means for attaching said pre-cast
member to the roadway member, whereby said roadway member forms a
substantially continuous reflective delineator which is protected from
normal wear and reliably exhibits reflecting properties both under dry
and rainy weather conditions.
10. A safety roadway delineator as defined in claim 9, wherein said
roadway member comprised a roadway curb facing.
11. A safety roadway delineator as defined in claim 9, wherein said
roadway member comprised as bench panel used in a tunnel.
12. A safety roadway delineator as defined in claim claim 9, wherein
said roadway member comprises a median barrier.
13. A safety roadway delineator as defined in claim 9, wherein said
reflection means comprises retroreflective glass beads.
14. A safety roadway delineator as defined in claim 9, wherein said
roadway member includes at least two recessed marker surfaces spaced
from and parallel to each other and each provided with reflection
means.
15. A safety roadway delineator as defined in claim 9, wherein said
roadway member includes at least two recessed marker surfaces each
provided with reflection means.
16. A safety roadway delineator as defined in claim 15, said two
recessed marker surfaces are disposed at different angles in relation
to the horizontal.
17. A safety roadway delineator comprising an elongate roadway member
forming a barrier extending along and at least partially defining the
roadway; a pre-cast polymer concrete member having an exterior surface
facing the roadway and exposed to roadway traffic, said pre-cast member
being provided with a generally elongate marker surface recessed in
relation to said exterior surface, said marker surface extending along
the length direction of said roadway member and being inclined in
relation to the horizontal to cause water run-off; reflection means
applied to said recessed marker surface for at least partially
reflecting incident light in the direction of the source of incident
light on the roadway, said roadway member comprising a cast-in-place
concrete roadway member and said pre-cast member being formed as a
cast-in-place form and includes anchor means attached to said
cast-in-place concrete roadway member, whereby said roadway member
forms a substantially continuous reflective delineator which is
protected from normal wear and reliably exhibits reflecting properties
both under dry and rainy weather conditions.
DESCRIPTION:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention generally relates to highway structures and more
specifically to a safety roadway delineator which is substantially
immune from normal wear and reliably exhibits reflectivity both under
dry and rainy night-time weather conditions.
2. Description of the Prior Art
Reflective stripes and other markings have been provided on highways
and highway structures, such as curbs and median barriers, in order to
delineate or identify the boundaries of a highway or to divide lanes on
a multi-lane highway. One of the major problems with such delineators
has been their visibility under different driving or weather
conditions, on the one hand, and the durability of such markings or
stripes, on the other hand.
While such delineators function properly and efficiently under ideal
driving or weather conditions, their usefulness frequently deteriorates
during inclement weather, particularly when it rains. Under such
adverse conditions, the delineators are frequently not clearly visible
and this poses a danger or hazard to those using the highway or road.
The problem and the need for a solution have been discussed by
transportation engineers and others who are involved with the design,
construction and maintenance of highways. See, for example, "ITE
Hearing Record--Performance Standards For Retroreflectivity Of Traffic
Control Devices", Institute of Transportion Engineers, Aug. 21, 1985;
and "Operation, Safety and Maintenance Of Transportation Facilities",
Transportation Research Circular No. 306, June, 1986, Transportation
Research Board, National Research Council. In the foregoing
publications, there is discussed the need to improve markings for
highways, particularly under wet or rainy night-time driving
conditions.
With the introduction of relatively durable paints and applied
plastics, along with the advent of retroreflective glass microspheres,
a partial solution to night-time traffic delineation has become
available. However, these techniques still have certain drawbacks. For
example, reflective markers or delineators which are exposed to normal
traffic will wear down or be adversely effected by inclement weather,
road salt and corrosive and chemical attack, and mechanical snow
removal equipment. Additionally, during wet or rainy weather driving
conditions, water causes the refractive and reflective light indices to
change for both reflective beads and the base materials. In some cases,
the wetting of such reflective materials cause the total visual
disappearance of the demarcation elements. Such visual deviation is due
to a "mirror" effect of the headlights impinging upon the water on the
reflective material instead of directly on the reflective material
itself. All of these disadvantages are true not only of roadways, but
also curbs, median dividers, and other traffic routing devices.
Numerous solutions have been proposed for achieving the goal of
providing a reliable highway delineator which functions satisfactorily
both during ideal as well as during inclement weather conditions. For
example, in U.S. Pat. No. 2,345,644, issued to Weber on Apr. 4, 1944,
there is described a light reflecting sign or marker which utilizes a
Portland cement base poured on site and relatively large glass
reflective beads are imbedded in a pre-cast panel of white Portland
cement which is imbedded in the cement curb. However, the panel is
disposed at the exterior surface of the cement base which is exposed to
the vehicular traffic. The glass beads, in fact, project beyond the
surface and, therefore, are susceptible to contact with vehicles and,
therefore, the probability that such glass reflective beads will be
dislodged is substantial.
In U.S. Pat. No. 3,203,327, issued to Daley on Aug. 31, 1965, a cast
metal street curb is disclosed which includes vertical ribs or
recesses. Although the patentee does not show reflective material
within such recesses, he does mention that it is possible to provide
paint or a similar finish in order to enhance the visibility of the
curb to motorists at night. However, Daley does not teach or suggest
the use of elongate horizontal delineators which run generally parallel
to the road and which are recessed and provided with retroreflective
materials in order to enhance the amount of reflection under adverse
weather conditions.
U.S. Pat. No. 4,000,882, issued to Penton on Jan. 4, 1977, discloses a
contrasting marker panel for highway guardrails. Penton intends,
however, to utilize his invention with the most commonly used form of
continuous guardrail which is formed of sheet iron or steel. Penton
utilizes a marker panel which is receivable within the trough of the
guardrail and covered with a plastic film. Penton suggests that such
plastic film may sometimes be reflectorized and also suggests that a
reflector or reflectors may, in certain instances, be mounted within
the trough so as to be exposed outwardly of the guardrail recess.
The Penton marker panel is not, however, suitable for use in connection
with other highway safety structures, particularly those made of
cast-in-place concrete or pre-cast elements.
SUMMARY OF THE INVENTION
One object of the invention is to provide a roadway delineator which
overcomes the disadvantages inherent in prior art reflective markers
and delineators.
It is another object of the present invention to provide a roadway
delineator which is simple in construction and inexpensive to
manufacture.
It is still another object of the present invention to provide a
roadway delineator which is substantially immune from normal wear.
It is yet another object of the invention to provide a roadway
delineator of the type under discussion which will provide reliable
reflectivity and guidance for vehicular traffic in rain and night-time
conditions.
It is a further object of the invention to provide a roadway delineator
which can be used in a variety of applications and with different
roadway structures.
It is still a further object of the invention to provide a roadway
delineator which has a great deal of flexibility and can be
incorporated into highway structures both on site or in pre-cast
structures which can be brought to the site.
It is an additional object of the invention to provide a roadway
delineator which can be used with a variety of different reflecting
materials, and particularly with retroreflective materials.
In order to achieve the above objects, as well as others which will
become apparent hereafter a safety roadway delineator in accordance
with the present invention comprises an elongate roadway member forming
a barrier which extends along and at least partially defines the
roadway. The roadway member has an exterior surface which faces the
roadway and is exposed to the roadway traffic. Said roadway member is
provided with a generally elongate marker surface recessed in relation
to said exterior surface. Said marker surface extends along the length
direction of said roadway member and is inclined in relation to the
horizontal to cause water run-off. Reflection means is provided which
is applied to said recessed marker surface for at least partially
reflecting incident light in the direction of the source of incident
light on the roadway. In this manner, said roadway member forms a
substantially continuous reflective delineator which is protected from
normal wear and reliably exhibits reflectivity both under dry and rainy
weather conditions.
Advantageously, the safety roadway delineator in accordance with the
invention utilizes a retroreflective material, such as glass
microspheres which are set into a very durable material whose adherence
depends both on a chemical as well as a mechanical bond. The base
material into which the reflective material is set advantageously
exhibits outstanding strength characteristics as well as being chemical
and weather resistant. As noted, further protection from physical
damage to the microspheres is attained by recessing the implant so as
not to have the retroreflective area within the proximity of normal
wear due to scraping tires, wheel rims, road sweeping vehicles or snow
removal equipment.
An important feature of the present invention is that the recessed
surface to which the reflective material is applied is vertical or
inclined in relation to the horizontal to cause water run-off and
insure that the reflective material is not subjected to the "mirror"
effect and a deterioration of the reflective characteristics due to
rain or wet conditions, this insuring continued safe night-time driving
during inclement or rainy weather conditions.
The invention provides continuous edge, or island, or bridge
demarcation and is helpful to minimize depth perception difficulties
encountered with other prior approaches.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention together with other and
further objects, features and advantages thereof, as well as other
characteristics of various embodiments thereof, reference is had to the
following description taken in conjunction with the accompanying
drawings in which:
FIG. 1 is a perspective view of a pre-cast reflective polymer concrete
curb form in accordance with the present invention, partially broken
away to illustrate how the pre-cast concrete section is attached to a
cast-in-place concrete structure.
FIG. 1a is a cross-section of the pre-cast reflective marker as viewed
along lines 1a--1a of FIG. 1;
FIGS. 2-5 illustrate different angles of inclination in relation to the
horizontal of the recessed marker surfaces, each of which provides
desired water run-off;
FIGS. 6-10 illustrate different roadway members made of cast-in-place
concrete and provided with pre-cast facing panels formed with the
recessed marker surfaces, all of the elongate marker surfaces being
vertical with the exception of the one shown in FIG. 8, which is
inclined at approximately 45° to the horizontal. FIG. 10 also
illustrates the use of two pre-cast members spaced one above the other
on the concrete road structure to provide two reflective roadway
delineators one above the other;
FIGS. 11-15 illustrate roadway members similar to those shown in FIGS.
6-10, respectively, but showing the elongate marker surfaces formed
directly in the cast-in-place concrete roadway members and not on
separate pre-cast elements or facing panels;
FIG. 16 is a front elevational view of typical low and high bench
panels used in tunnel constructions, illustrating the manner in which
the present invention is incorporated in pre-cast polymer concrete
members which are attached to cast-in-place concrete structures;
FIG. 17 is similar to FIG. 16, except that the elongate marker surfaces
are formed directly in the cast-in-place concrete;
FIG. 18 is a front elevation view, in section, of a typical
construction of a bridge rail or pedestrian walkway, showing how a curb
facing in accordance with the present invention may be attached to the
cast-in-place concrete curb;
FIG. 19 is similar to FIG. 18, except that the elongate marker surface
is provided and recessed directly in the cast-in-place concrete
structure.
FIG. 20 is a perspective view of a two-sided median barrier of the type
used as a divider between lanes, showing upper and lower elongate
recessed marker surfaces on each side of the median barrier and also
shown filled with concrete;
FIG. 21 is a perspective view of a one-sided median barrier of the type
which faces a single lane, shown abutting against a concrete wall, and
showing two elongate recessed marker surfaces, the lower one of which
is vertical, and the higher one of which is inclined at an angle in
relation to the horizontal; and
FIGS. 22 and 23 are similar to FIGS. 20 and 21, except that the
recessed elongate marker surfaces are formed directly in cast-in-place
concrete.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now specifically to the figures, in which identical or
similar parts are designated by the same reference numerals throughout,
and first referring to FIG. 1, a roadway member in accordance with the
present invention is generally designated by reference numeral 10.
The roadway member 10 forms a barrier which extends along and at least
partially defines the roadway 12. Specifically, the roadway member 10
shown in FIG. 1 is a curb which can be made in any known or
conventional way and is shown in FIG. 1 to be formed of cast-in-place
regular concrete 14. In accordance with the present invention, there is
provided a pre-cast member or element 16 which is attached to the
concrete member 14 by means of anchors 18 or in any other known or
conventional manner.
As will become apparent hereafter, the specific material from which the
element 16 is formed is not critical. However, it is presently
preferred that the element or member 16 be of reinforced pre-cast
polymer concrete. It has been found that polymer concrete is
particularly suitable for the intended purpose. Polymer concrete is a
hybrid product which exhibits improved performance characteristics over
regular concrete or cementitious materials. Polymer concretes are
generally lighter in weight, exhibit increased tensile and compresive
strength, and generally have a higher resistance to moisture and other
corrosive elements. Polymer concrete does not contain cement and is
made up of various binders, such as polyesters of numerous types of
long chain monomers, epoxies, methyl methacrylates, urethanes and
vinylesters. Because the viscosities of these binders differ, the
amounts, sizes and proportions of the fill may vary with each
particular polymer. Thus, determining which binder to use is usually
based on strength desired and cost considerations. Different polymer
concretes can be used in connection with the present invention, with
different degrees of advantage.
Polymer concrete produced by Transpo Industries, Inc., Castek Division,
has been successfully used to produce the pre-cast polymer concrete
roadway delineators in accordance with the invention. Polymer concretes
are discussed in a brochure entitled "Polymer Concrete--The State Of
the Art", an information bulletin from Transpo Industries, Inc., the
Assignee of the subject application.
Still referring to FIG. 1, the roadway member 10 is an elongate member
the length direction of which extends substantially parallel to the
roadway 12. The pre-cast polymer concrete member or facing panel 16 has
an exterior surface 20 which faces the roadway 12 and is exposed to
roadway traffic. A generally elongate marker surface 22 is provided on
the facing panel 16 recessed in relation to the exterior surface 20.
The marker surface 22 preferably forms an elongate line which extends
along the length direction of the facing panel 16 and is inclined in
relation to the horizontal to cause water run-off. In the roadway
member 10, the recessed marker surface 22 is in a vertical plane or
inclined 90° in relation to the horizontal. This configuration,
clearly, provides maximum water run-off. However, smaller angles can be
used with similar advantage. Although the recessed marker surface 22 is
shown as a continuous line in FIG. 1, as well as in the remaining
figures, it should be clear that the present invention also
contemplates a continuous marker surface which is intermittently or
periodically interrupted to form an elongate discontinuous reflective
surface.
An important feature of the invention is the provision of reflection
means applied to the recessed marker surface 22 for at least partially
reflecting incident light in the direction of the source of the
incident light on the roadway. Although any one of numerous reflective
materials may be used, it is presently preferred that retroreflective
materials be applied to the recessed marker surface 22, such as
reflective glass beads 24. Prismatic materials (sheeting) can also be
used to provide retroreflectivity. Glass beads, because of their
spherical configuration have a much larger range of entrance angles for
which retroreflectivity will be exhibited. The use of retroreflective
materials and, glass beads, in particular, are well known to those
skilled in the art.
The facing panel 26 is shown in FIG. 1 to have a length 26, a thickness
27, and a height 28. These dimensions of the facing panel are not
critical. For curb applications, the height of the facing panel 16 can,
for example, be between 12 to 18" in height and 4-8' in length. Since
highways and roads can extend for many miles, a plurality of such
facing panels 16, each of which is pre-cast, may be arranged end-to-end
to each other to form a substantially continuous barrier, and the
recessed marker surfaces aligned with each other to form a
substantially continuous reflective delineator. In the case of
cast-in-place concrete versions of the invention, it is possible, in
theory, to use a continuous roadway member extending along the entire
length of the highway or road.
As above noted, the elongate recessed marker surface 22 is inclined in
relation to the horizontal to cause water run-off to prevent the
"mirror" effect and a deterioration of the retroreflective properties
of the reflecting material. In order to eliminate or minimize this
"mirror" effect, it is imperative that any rain or water which comes
into contact with the reflective material be prevented from
accummulating and covering the reflective material. Referring to FIGS.
2-5, four different examples are shown in which the recessed marker
surfaces 22a-22d are inclined at successively smaller angles θ[a] -θ[d]
in relation to the horizontal. The facing panels 10a-10d are all
effective in draining the rain or water from the reflective surfaces.
Clearly, the greater the angle in relation to the horizontal, the more
rapid the run-off and, therefore, the less likely of any appreciable
accummulation of water covering the reflective material during heavy
rain. The inclination of the recessed marker surfaces 22a-22d also has
the advantageous feature that water run-off washes or cleans the
reflective surface, such as the reflective beads, and this
self-cleaning action maintains the reflective surface at optimum or
near-optimum reflecting condition.
Referring to FIGS. 6-10, five typical roadway structures 10e-10i are
shown, each of which is formed by cast-in-place concrete to which one
or more pre-cast polymer concrete facing panels 16 are attached each
with a recessed marker surface 22a. In the case of FIG. 10, the roadway
member 10i is provided with an upper facing panel 16a and a lower
facing panel 16b to provide elongate vertically spaced roadway
delineators in accordance with the present invention. As will be noted
from FIGS. 6-10, the present invention is extremely flexible and can be
used in connection with almost every roadway member irrespective of
size or shape. FIGS. 11-15 are similar to FIGS. 6-10 and illustrate the
same types of roadway members. However, separate facing panels are not
used in FIGS. 11-15. Instead, the recessed marker surfaces 22a and 22c
are formed directly in the cast-in-place concrete members. This can be
done during the molding process for new installations. To modify an
existing installation, any conventional equipment, such as grinders,
can be used to remove a thickness of the concrete to produce the
recessed marker surfaces. The roadway structures in FIGS. 11-15 are
designated by references 10e'-10i', which correspond to the roadway
members 10e-10i in FIGS. 6-10.
In FIG. 16, there is shown a tunnel 10j through which the roadway 12
passes. For purposes of illustration, a low bench panel 32 is shown
with a first reflective surface 22a substantially at the level of the
roadway 12, and a second reflective surface 22a just above the first
reflective surface. The positions of the reflective surfaces is not
critical for the purposes of the present invention and their locations
will vary depending on the application. In the case of the high bench
panel 34, a first reflective surface 22a is formed in the facing panel
16a in the upper region of the bench panel 34. A second reflective
surface 22a is formed in the lower facing panel 16b which is
substantially at the level of the roadway 12. In FIG. 17, low bench
panel 32' corresponds to the panel 32 in FIG. 16 and the high bench
panel 34' corresponds to the bench panel 34 in FIG. 16. The tunnel 10k
constructions are similar, therefore, to those in FIG. 16 with the
exception that the reflective surfaces are formed directly in the
concrete and separate facing panels are not utilized.
Referring to FIGS. 18 and 19, bridge rail and pedestrian walkways 101
and 101' are shown which are similar in construction to the curb
constructions shown in FIG. 1. In FIG. 18, a polymer concrete facing
panel 16 is utilized, while in FIG. 19, the reflecting surface 22a is
formed directly in the concrete. Also shown in these figures is an
overlay 36 which is applied to the roadway after the curb facing panel
16 is attached by means of anchors 18 or other suitable means to the
roadway.
Referring to FIGS. 20 and 21, there are shown pre-cast polymer concrete
median barriers 38 and 40. In FIG. 20, the median barrier 38 is a
two-sided median barrier which can be used as a divider between lanes.
Being pre-cast and transported to the site of use, the median barrier
38 is advantageously initially made hollow to reduce its weight and
filled with concrete 14 at the site. The barrier 38 is provided with an
upper marker surface 22e and a lower marker surface 22f, these being
provided on each side of the median barrier so that similar roadway
delineators are visible in each of the lanes separated by the barrier.
In FIG. 21, a one-sided median barrier 40 is shown which faces only one
lane, and may abut against a concrete wall or the like. Here, the
median barrier 40 is provided with a lower marker surface 22f and a
slightly higher marker surface 22g which is inclined at an angle less
than 90° from the horizontal. It should be clear that one, two or more
marker surfaces may be provided on each roadway member oriented and
spaced from each other in any desired fashion.
In FIGS. 22 and 23, median barriers 38' and 40' are shown which are
similar to those shown in FIGS. 20 and 21, respectively, except that
the median barriers are formed of cast-in-place concrete and the
recessed marker surfaces are formed directly in the concrete without
the use of separate facing panels.
While preferred embodiments of the invention have been shown and
described herein, it is obvious that numerous additions, changes and
omissions may be made in the invention without departing from the
spirit and scope thereof. Thus, for example, while it is presently
preferred that the marker surfaces be inclined in relation to the
horizontal at an angle of at least 45°, any suitable angle selected for
a particular application may be used.